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在严重事故下,氢气和水蒸气在安全壳局部隔间内释放,并通过相对窄小的流道向其他隔间流动迁移,气体与隔间壁面之间的换热过程对氢气分布有重要影响.本文采用计算流体力学(CFD)方法对安全壳内具有竖直连接结构特点的局部隔间建立分析模型,分别讨论了基于类比理论的Von Karman类比、Reynold类比和直接类比三种对流换热模型对隔间内压力变化、壁面凝结换热量、氢气和蒸汽浓度分布情况的影响.结果表明,采用Von Karman类比和Reynold类比模型所获得的局部隔间整体的蒸汽壁面凝结量以及气体流动行为基本保持一致,采用直接类比模型模拟的蒸汽凝结量比前两种模型更多.大部分蒸汽凝结发生在有源隔间顶部壁面,直接类比模型对此处凝结量的模拟高于Von Karman类比和Reynold类比模型,由此导致有源隔间内气体温度降低,浮力驱动下氢气向无源隔间的迁移也相应减弱,使得无源隔间内的氢气浓度较小.“,”During the severe accident process, the hydrogen and the steam are released into the containment and transferred to other local compartments through narrow pipes. Heat transfer between gas mixture and wall has influence on hydrogen distribution. In this paper, CFD method is adopted to build the analysis model for local compartment connected by vertical flow path in the containment. The effect of Von Karman model, Reynolds model, and directly similar v-t profile model based on analogy theory on pressure, condensation heat, hydrogen and steam distribution are discussed. The result shows that the steam condensation mass and the hydrogen flow behavior simulated by Von Karman model and Reynolds model is consistent. The condensation mass obtained by directly similar v-t profile model is higher. Most steam condensed on the top wall of the source compartment, on this wall, directly similar v-t profile model predicts more condensation than other two models, which results in lower gas temperature. Hydrogen transferring into the upper compartment driven by buoyancy is also weaker. The hydrogen concentration in this compartment is lower.